Structure-Activity Relationships, Pharmacokinetics, and Pharmacodynamics of the Kir6.2/SUR1-Specific Channel Opener VU0071063
作者:Sujay V. Kharade、Juan Vicente Sanchez-Andres、Mark G. Fulton、Elaine L. Shelton、Anna L. Blobaum、Darren W. Engers、Christopher S. Hofmann、Prasanna K. Dadi、Louise Lantier、David A. Jacobson、Craig W. Lindsley、Jerod S. Denton
DOI:10.1124/jpet.119.257204
日期:2019.9
Glucose-stimulated insulin secretion from pancreatic β -cells is controlled by ATP-regulated potassium (KATP) channels composed of Kir6.2 and sulfonylurea receptor 1 (SUR1) subunits. The KATP channel-opener diazoxide is FDA-approved for treating hyperinsulinism and hypoglycemia but suffers from off-target effects on vascular KATP channels and other ion channels. The development of more specific openers would provide critically needed tool compounds for probing the therapeutic potential of Kir6.2/SUR1 activation. Here, we characterize a novel scaffold activator of Kir6.2/SUR1 that our group recently discovered in a high-throughput screen. Optimization efforts with medicinal chemistry identified key structural elements that are essential for VU0071063-dependent opening of Kir6.2/SUR1. VU0071063 has no effects on heterologously expressed Kir6.1/SUR2B channels or ductus arteriole tone, indicating it does not open vascular KATP channels. VU0071063 induces hyperpolarization of β -cell membrane potential and inhibits insulin secretion more potently than diazoxide. VU0071063 exhibits metabolic and pharmacokinetic properties that are favorable for an in vivo probe and is brain penetrant. Administration of VU0071063 inhibits glucose-stimulated insulin secretion and glucose-lowering in mice. Taken together, these studies indicate that VU0071063 is a more potent and specific opener of Kir6.2/SUR1 than diazoxide and should be useful as an in vitro and in vivo tool compound for investigating the therapeutic potential of Kir6.2/SUR1 expressed in the pancreas and brain.
胰岛β细胞在葡萄糖刺激下分泌胰岛素是由Kir6.2和磺脲受体1(SUR1)亚基组成的ATP调节钾(KATP)通道控制的。KATP 通道开启剂二氮卓获 FDA 批准用于治疗高胰岛素症和低血糖症,但对血管 KATP 通道和其他离子通道有脱靶效应。开发更具特异性的开放剂将为探索 Kir6.2/SUR1 激活的治疗潜力提供急需的工具化合物。在这里,我们描述了我们的研究小组最近在高通量筛选中发现的一种新型 Kir6.2/SUR1 支架激活剂。VU0071063 对异源表达的 Kir6.1/SUR2B 通道或动脉导管张力没有影响,表明它不会打开血管 KATP 通道。VU0071063 能诱导β细胞膜电位超极化,抑制胰岛素分泌的作用比二氮醇更强。VU0071063 具有有利于体内探查的代谢和药代动力学特性,并且具有脑穿透性。服用 VU0071063 可抑制葡萄糖刺激的小鼠胰岛素分泌和降糖。总之,这些研究表明,VU0071063 是一种比二氮醇更有效、更特异的 Kir6.2/SUR1 开释剂,可作为一种体外和体内工具化合物,用于研究在胰腺和大脑中表达的 Kir6.2/SUR1 的治疗潜力。